Balance Sheet Items - Schedule of Other Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Patent cost reimbursements	$ 3,377	$ 4,702
Accrued interest on marketable securities	436	226
Other	356	555
Total	$ 4,169	$ 5,483

Amount due from parties in nontrade transactions, classified as other.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_OtherReceivables
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant